Pulsator for pulsatory tools.



N I I v WIT/M8858. llVl/E/VTUR I CQQAQM.C Q Ox. Q 6.3mm By 0. A. DAWLEY.

PULSATQR FOR PULSATORY TOOLS. APPLIOATION FILED MAR. 26. 1912.

1,126,959,, Patented Feb. 2, 1915.

- ED s'rA'rEs PATENT OFFICE.-

CLARENCE A; nAw EY, or rhanvr'mpn, lvnw a'ansnv, nssrenoza r INGERSOLL-RAND comrmr, or NEW YORK,- n; Y., A conroRArIoN or NEW JERSEY.

runsa'ron ron rULsAronY TOOLS.

To all whom it may concern Be it known that I, CLAREN E a citizen of the United States, residing 1n Plainfield, in the county of Union and State ments in Pulsators for Pulsatory Tools, of whichthe following is'a speclfication.

quired in the front endof the toolcylinder -This invention relates to pulsators for" pulsatory tools and more particularlyio a double cylinderpulsator adapted for use with tools of the free piston or hammer type. .In the double cylinder pulsators heretofore used the cylindershave both developed the same compression, furnishing equal power to both sidesof the *tool operated thereby, either becausewhen' independent, the cylinders were of the same design or when connected the cylinders both opened into the same crankcase-and drew-from the same air supply.- 'In the operation of ham- .mer tools however very. little power is reon account of the rebound of the piston, and hence thepressure in-this- -end of the tool cylinder can advantageously :be less than in the back end. This result can only be obtainedeflectively byhaving'a pulsatorwith two 4 pressure spaces maintained at different pressures. 1 i

The "bject of the present invention is to provide a pulsator wherein this result is obtained, and to thisend, I fill-ave devised apulsator," a practical embodiment ojf-which is -shown the accompanyingdrawings m Figure 1 is a side elevation partly m sec- :tion of the complete puisator.- -1 Tig.-2 is a sectional view showing a detail .o fthepiston and crank construction.

Thepulsator. as shown comprises a high pressure cylinder land a low pressure cylinder 2. In the cylinders are pistons 3 and I 4 which are operated by rods' 5 and 6,

the head of each is pivotally held as-shown in c linder 1 in Fig.1 and in Fig. 2 by a pm which bridges a recess 8 in thepiston. This construction is used in order-that the crank end ofthe piston shallhave as [little clearance vas possible. The other ends of rods 5 and 6 are attached 'to crank pins -9 and 10,- which are mounted on crank disks 11- and 12. These crank disks are rotated by the shaft 13 of a motor 14. In the present Specification of Letters 1 atent.

A. DAWLEY,

and port-33 should be open.

Patented Feb. 2, 1915.

Applibation filed March 216, 1912. Serial No. 686,432.

case they are shown as directly connected to the shaft of the motor although of course intermediate gearing may be used.

1 In order tomaintain the two cylinders at different pressures one end of each, in this case the back ornfree end, is used as a tool operating chamber while the front or crank ends of the cylinders are constructed to operate as pumps, their different clearances giving different pressures. To obtain this result the crank cases 15'and 16 are made air tight, the crank case 15 on the highpressure cylinder forming a clearance chamber 17 smaller than the low pressure cylinder clearance chamber 18. Air isadmitted into the clearance spaces through check valves 19 and 20 which open into the clearances at any de-' sired-points.- 'In order to convey air from oneside of the piston to the other to build up the pressure in the tool operating pressure chambers, ports 21 and 22. are provided which just bridge the .pistons'at the lowestv point of their strokes. 7

'As an additional means ofbuilding .up pressure the high pressure cylinder, when a highen pressure is desired than is practicable on account of thenecessary size of the clearan'ce space 17, air may be taken. into it from the low pressure cylinder, which is inder, these-ports being controlled bycheck valves27 and 28. which can be adjusted or closed byscrews 2,9 and 30 'The high pressure cylinderg'is provided with a valve chest 31 from which ports 32 and 33 lead to the cylinder, the lower port, 33 having a screw 34 ada'pted-to-clo'se it. v

From the upper ends of cylinders which form the pressure chambers for operating the tool fluid conduits 35 and 36 lead to the opposite'sides of the piston of the tool to be operated. (Not shown.) I

In operation the pulsator may be used in a variety-of ways. When it is desired to maintain alarge difi'erence in pressure between the. cylinders the check valve at port 25-should be seated as lightlyas possible On the up stroke of piston 4 air will be drawn in through valve 20 from the atmosphere. On

25 a v ing down adjusting screws .29 and 30. In

the down stroke'o'f piston 4 the air will be H compressed in the crank case '16 and W111 (reach its maximum pressure just before the At the end of the down 'strol e of piston 3 the pressureson botlfsides of piston 3 will equalize, thus allowing air to flow into the tool operating end of cylinder 1. In this way the pressure will he stepped up 1n the high pressure cylinder, until the. pressure in thecrank end of the cylinder 1 at substantially the end of its up stroke is equal to the maximum pressure possible in crank case 16 which is limited of course by the size of the clearance in this cylinder, the pressure at the end of the up stroke of piston 4 never being greater than atmospheric pressure.

If it is desired to maintain a smaller difference in pressures between the cylinders, the ports 25 and 26 can be closed by screwthis case the difference in pressure in the two. cylinders will be caused by the difl'erence in the size of the clearance spaces in the crank ends of the cylinders. The clearance space in cylinder 1 being smaller than in cylinder 2, a greater pressure can be built up in this cylinder as the check valves. 19 and 20 allow the ressure at the end of the up stroke' of eac piston to reach atmospheric pressure.

All gradations of difference in pressure between the two mentioned above can be obtained by adjustingvalves 27 and 28 by means of scr'ews 29 and 30.

If it is to be desired to operate both cylinders of the pulsator at the same pressure, port 33. can be opened and check valve 27 temporarily removed or otherwise arranged.

to allow port 25 to bfully opened. 00

paratively little pressure will be built up 1n the system in this way, thetool operating at very little above atmospheric pressure. The

check valves 19 and 20 prevent any part of the system from going below atmospheric pressure however.

.Although the pipe 23 and valve chests 24 and 31 areshown as a means for increasing the pressure difference between the cylinders beyond that which can be obtained by dif-' ferences in the clearance spaces of the cylinder, nevertheless where a smaller range of diiferences between the'pressures in thecylinders is required or where stil higher pressure in the whole system is desired, both the cylinders may have the same clearance. and the checkvalves 27 and 28 and pipe 23 alone depended on to produce the difference in pressure between the two cylinders.

It is to be understood that the device as for supplying fluid under pressure to the conduit having check valve mechanism therecylinders, one end of each of said cylinders and the other end a pressure building pump.

shown and described discloses only one modification of my pulsator and other changed and modified forms are included within the spirit and scope of my invention as expressed in the claims.

What I claim is:

1. In a pulsator for pulsatory tools, the combination of two cylinders, pistons in said cylinders, one end of "each of said cylinders forming a tool operating pressure chamber ing diflerent clearances, and supplyli ng fluid at different pressures to said pressu e chambers, and means for supplying fluid under pressure from the cylinder of lower pressure to the pump sure;

3. In a pulsator for pulsatory tools, the combination of two cylinders, pistons in said cylinders, one end of each of said cylinders forming a tool operating pressure chamber of the cylinder of higher presand the other end a pressure building pump for supplying fluidunder pressure to one of said pressure chambers, and means for supplying fluid under pressure from one of said cylinders to the pressure building pump of the other. v 4. In a pulsator forapulsatory tools, the combination of two cylinders, pistons in said cylinders, one end of, each of said cylinders forming a tooloperating pressure chamber, and'the other end a pressure building pump corresponding press'urechamber, and'a fluid in leadingfrom one cylinder to the pressure building pump of the other whereby fluid already under pressure is supplied to the pump of the second cylinder.

-5. In a pulsator for pulsatory tools, the combination of two cylinders, pistons in said forming a tool operating pressure chamber,

for supplying fluid under pressure to the corresponding pressure chamber, said pumps having different clearances and adapted to supply fluid to and maintain their respective pressure chambers at diflerent pressures, and a fluidconduit connecting said pumps.

6. Ina pulsator for pulsatory tools, the combination of two cylinders, pistons in said cylinders, one end of each of said cylinders forming s tool operating pressure chamber corresponding pressure chem er, a fluid conpumps having'di erent'clearanoes.andodapted to supply fluid to and maintain theirre i speetive ressure chambers atdifierent pressures, a uid Conduit connecting said pumps,- said oondu'it having adjustable ohek valve mephafiism therein-to alldw fluid to puss from-the lower'to. the'higher pressure cylduit connecting said pumps, said conduit hayin a plurality of ports leading intoone of 311i pumps and check'valves controlling sal orts. 4 1 7. n e pulsatorfor. pulsatory tools, the combination of two cylinders, p1stons in said cylinders, one end of-e'ach of said eylinders forminge tool operating pressure chain' her and the other end a pressure building pu mp for supplying fluid under pressure :to

the correspondin pressure chamber, said inder;

tvvo pressure building'p'umps forsa-id 1p sure chambers, Tend means for ,supp ymg 8. e pulsator for pulsatory vtoolsg the combination of tyvo cylinders, and pistons in said cylinders, the ends ,of said cylinders formingitw'o tool operatin' "pressure-chamhers and two ressure -bu1 d ng pum s forsaid pressure 0 amberfsi said pressure. "uildmg pumps having di erent clearances and "supplying fluid at different pressurestor' maintain e xdiiference-in pressure between;

said chambers.

'9. In a; ,pulsator two tool operating pressure ehambershn fluid under pressure from one'of -said surebuilding punips.to thefothetg p A- ENCEAMWLEY BMW; 1

I M C K m f r masseuse; the T -3 5.

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